This invention generally relates to devices for protecting the integrity of a sharpened cutting edge on a tool and for protecting the operator as user of the tool. In particular the invention relates to a protective device for sharp blades such as those used in rotating machinery used for shearing.
In machinery using rotating cutting blades in which one edge is a sharpened edge it is frequently necessary to work near the cutting edge of such a blade. In some circumstances it is necessary to restrain the blade from rotating while removing it from or attaching it to the machinery. While performing sharpening operations it is also necessary to restrain the blade from rotating without removing the blade.
In handling such cutting edges, in particular in devices such as rotary lawn mowers, it is necessary to block the blade from rotation by inserting physical restraints such as wood blocks or metal bars between the blade and the housing in which it rotates. This procedure has the disadvantage of possibly dulling the blade by forcing it against a hard surface such as a steel bar and increases the risk of injury to the operator which is always present when dealing with an exposed sharpened edge. This is particularly true when removing or installing blades in rotary machines or where it is necessary to remove restraining devices in order to remove the blade from the machine.
The present invention overcomes these disadvantages by providing a portable, removable protective cover for the cutting edge of the blade. In addition, where the blade is a double edge blade having cutting edges on opposite ends of a rotating arm there is provided a separate covering for each of the cutting edges and a means for connecting the coverings to insure their retention on the cutting edge.